title: Esterase patterns in four Brazilian populations of Haematobia irritans.
abstract: Four population samples of Haematobia irritans (horn flies), collected from farms and subjected, or not, to insecticide control, were analysed as to esterase bands by polyacrylamide gel electrophoresis. Eight esterase bands were detected in this species, a low number when compared with flies of other genera. The reduced number of esterase variants of H. irritans is attributed to their parasitic behaviour and blood-dependence for food. Unlike other fly species whose esterase bands exhibit affinity to both alpha- and beta-naphthyl acetates, the esterases in H. irritans seem to be of a single kind, all preferentially hydrolysing alpha-naphthyl. The four populations were very similar as to esterase bands. In relation to the frequencies of patterns resulting from combining bands, Nova Aliança and Birigui were more alike than the other two populations. Inhibitors were used in an attempt to classify five of the esterase bands. The results indicate one acetylcholinesterase, two acetylesterases and two carboxylesterases.
authors.affiliation: Departamento de Biologia, Universidade Estadual Paulista-UNESP, São José do Rio Preto, SP, Brazil.
authors.forename: L
authors.initials: L
authors.lastname: Castiglioni-Ruiz
authors.forename: H E
authors.initials: HE
authors.lastname: Bicudo
authors.forename: C R
authors.initials: CR
authors.lastname: Ceron
mesh_terms: D000818:Animals; D001938:Brazil; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004950:Esterases / Q000032:analysis* / Q000037:antagonists & inhibitors; D005260:Female; D007306:Insecticides; D007527:Isoenzymes / Q000032:analysis*; D008297:Male; D009117:Muscidae / Q000201:enzymology*
chemical_list: D004791:Enzyme Inhibitors; D007306:Insecticides; D007527:Isoenzymes; D004950:Esterases